Page 1 of 1

Unichrome driver

Posted: Thu Sep 09, 2004 7:56 pm
by lmatter
This is a general thread for talking about using the Unichrome driver with minimyth.

I'll kick it off with this: ... _id=266463

Which is the readme for a patch to allow mythtv to use the unichrome driver.

The patch is hosted at the unichrome site on sourceforge.


Posted: Mon Sep 13, 2004 5:17 pm
by stevie-c
Seems that this driver is now default in Mythtv CVS and the libddmpeg/viaslice stuff was removed. Anybody out there who has unichrome working ?

Ivors message on the mythdev list :
unichrome is the name of the open source driver project for the via cle266, cn400 and kn400 chipsets (

XvMC is the motion compensation API used in nvidia cards to assist hardware decoding. The via chipsets provide a higher level mpeg decoding interface which provides VLD aka slice level decoding.
The unichrome driver has therefore implemented an extension to the XvMC api provisionally called XxMC (aka via XvMC aka XvVLD) to provide a nicer interface to the decoder.

This replaces the old via ddmpeg interface... which is no longer supported in the unichrome X drivers anyway.

The most noticeable impact of this change is that it is no longer necessary for mythfrontend to run as root.

As for "What do EPIA-M" users have to do.... well it depends. This change is in CVS and you're reading the dev list... so.... I guess "Needs Testing" about sums it up.

In brief... you'll need to be running X with the Unichrome drivers instead of the via drivers (see unichrome site). You'll need the libxvmc library installed (see unichrome site). and you'll probably need the unichrome drm drivers installed (see xorg).
Then you'll need to recompile myth and enable the XvMC_VLD option in your

Then start filing bug reports. :-)

Of course you might as well install the xine-plugin for unichrome too (see unichrome site) and play with mythdvd too.

Ivor. - Leylandii hedge, - Technology